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1.
Sensors (Basel) ; 24(18)2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39338625

RESUMO

Recent advancements in vehicle technology have stimulated innovation across the automotive sector, from Advanced Driver Assistance Systems (ADAS) to autonomous driving and motorsport applications. Modern vehicles, equipped with sensors for perception, localization, navigation, and actuators for autonomous driving, generate vast amounts of data used for training and evaluating autonomous systems. Real-world testing is essential for validation but is complex, expensive, and time-intensive, requiring multiple vehicles and reference systems. To address these challenges, computer graphics-based simulators offer a compelling solution by providing high-fidelity 3D environments to simulate vehicles and road users. These simulators are crucial for developing, validating, and testing ADAS, autonomous driving systems, and cooperative driving systems, and enhancing vehicle performance and driver training in motorsport. This paper reviews computer graphics-based simulators tailored for automotive applications. It begins with an overview of their applications and analyzes their key features. Additionally, this paper compares five open-source (CARLA, AirSim, LGSVL, AWSIM, and DeepDrive) and ten commercial simulators. Our findings indicate that open-source simulators are best for the research community, offering realistic 3D environments, multiple sensor support, APIs, co-simulation, and community support. Conversely, commercial simulators, while less extensible, provide a broader set of features and solutions.

2.
Environ Monit Assess ; 196(1): 102, 2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38158434

RESUMO

Planted forest soils can have great potential for CO2-C sequestration, mainly due to belowground C inputs, which impact deep soil C (DSC) accumulation. However, there are still gaps in understanding the CO2 emission dynamics in eucalypt plantations. Therefore, we used isotopic techniques to investigate the dynamics of the soil surface CO2-C flux and CO2-C concentration with depth for a eucalypt plantation influenced by different C inputs (above- and belowground). The gas evaluations were carried in depth the root to valuation of root priming effect (RPE) was calculated. In addition, measurements of the plant (C-fine root and C-litterfall) and soil (total organic carbon - TOC, total nitrogen - TN, soil moisture - SM, and soil temperature - ST) were performed. After planting the eucalypt trees, there was an increase in the soil surface CO2-C flux with plant growth. Root growth contributed greatly to the soil surface CO2-C flux, promoting greater surface RPE over time. In comparison to the other factors, SM had a greater influence on litterfall decomposition and root respiration. It was not possible to detect losses in TOC and TN in the different soil layers for the 31-month-old eucalypt. However, the 40-month-old eucalypt showed a positive RPE with depth, indicating possible replacement of DSC ("old C") by rhizodeposition-C ("new C") in the soil. Thus, in eucalyptus plantations, aboveground plant growth influences CO2 emissions on the soil surface, while root growth and activity influence C in deeper soil layers. This information indicates the need for future changes in forest management, with a view to reducing CO2 emissions.


Assuntos
Dióxido de Carbono , Solo , Dióxido de Carbono/análise , Monitoramento Ambiental , Florestas , Árvores , Carbono/análise
3.
Ophthalmologica ; 245(6): 528-537, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35853434

RESUMO

PURPOSE: The objective of this study wasto assess the prevalence of complete retinal pigment epithelium (RPE) and outer retinal atrophy (cRORA) in patients with unilateral exudative age-related macular degeneration (AMD) of the fellow eye and establish if the presence of non-exudative macular neovascularization (NE-MNV) influences the prevalence of RPE and outer retinal atrophy in eyes with AMD. METHODS: This is an observational cross-sectional study of 68 patients with unilateral exudative AMD. Demographic and clinical data were collected, and multimodal retinal imaging was performed in all patients. Two groups of patients were defined according to the presence (NE-MNV) or absence (no NE-MNV) of NE-MNV in the study eye. We compared the prevalence of tomographic cRORA and fundus autofluorescence (FAF) geographic atrophy (GA) and differences in cRORA greatest linear diameter (GLD) and GA area between groups. RESULTS: Globally, cRORA was present in 11 eyes (16.2%), FAF GA was present in 10 eyes (14.7%), and NE-MNV was present in 10 eyes (14.7%) of patients with unilateral exudative AMD of the fellow eye. The overall cRORA GLD was 1,950.64 ± 1,428.31 µm, and the mean area of GA was 9.25 ± 7.50 mm2. Regarding comparisons between groups, cRORA was present in 9 eyes (15.5%) without NE-MNV and in 2 eyes (20%) with NE-MNV (p = 0.66). Tomographic signs of atrophy were more frequent in eyes with NE-MNV (50% vs. 24.1% in eyes without NE-MNV; p = 0.008). No significant differences were found in cRORA GLD (p = 0.30) between groups. Eyes with NE-MNV and eyes without NE-MNV had a similar prevalence of FAF GA (2 eyes out of 10 and 8 eyes out of 58, respectively; p = 0.64). Eyes with NE-MNV had a smaller mean area of GA (2.07 ± 0.24 mm2 vs. 11.05 ± 7.34 mm2; p = 0.01). CONCLUSION: In our study, the presence of NE-MNV was not associated with the prevalence of cRORA and/or FAF GA. Nonetheless, eyes with NE-MNV presented smaller areas of GA, which suggests that this type of neovascularization may prevent the progression of RPE and outer retinal atrophy. Longitudinal studies are required to confirm these preliminary results.


Assuntos
Atrofia Geográfica , Epitélio Pigmentado da Retina , Humanos , Epitélio Pigmentado da Retina/patologia , Prevalência , Estudos Transversais , Angiofluoresceinografia/métodos , Tomografia de Coerência Óptica/métodos , Atrofia Geográfica/diagnóstico , Atrofia Geográfica/epidemiologia , Atrofia/diagnóstico
4.
Sensors (Basel) ; 22(19)2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36236653

RESUMO

Optical fiber sensors present several advantages in relation to other types of sensors. These advantages are essentially related to the optical fiber properties, i.e., small, lightweight, resistant to high temperatures and pressure, electromagnetically passive, among others. Sensing is achieved by exploring the properties of light to obtain measurements of parameters, such as temperature, strain, or angular velocity. In addition, optical fiber sensors can be used to form an Optical Fiber Sensing Network (OFSN) allowing manufacturers to create versatile monitoring solutions with several applications, e.g., periodic monitoring along extensive distances (kilometers), in extreme or hazardous environments, inside structures and engines, in clothes, and for health monitoring and assistance. Most of the literature available on this subject focuses on a specific field of optical sensing applications and details their principles of operation. This paper presents a more broad overview, providing the reader with a literature review that describes the main principles of optical sensing and highlights the versatility, advantages, and different real-world applications of optical sensing. Moreover, it includes an overview and discussion of a less common architecture, where optical sensing and Wireless Sensor Networks (WSNs) are integrated to harness the benefits of both worlds.


Assuntos
Fibras Ópticas , Temperatura
5.
Sensors (Basel) ; 22(22)2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36433181

RESUMO

Indoor positioning and navigation have been attracting interest from the research community for quite some time. Nowadays, new fields, such as the Internet of Things, Industry 4.0, and augmented reality, are increasing the demand for indoor positioning solutions capable of delivering specific positioning performances not only in simulation but also in the real world; hence, validation in real-world environments is essential. However, collecting real-world data is a time-consuming and costly endeavor, and many research teams lack the resources to perform experiments across different environments, which are required for high-quality validation. Publicly available datasets are a solution that provides the necessary resources to perform this type of validation and to promote research work reproducibility. Unfortunately, for different reasons, and despite some initiatives promoting data sharing, the number and diversity of datasets available are still very limited. In this paper, we introduce and describe a new public dataset which has the unique characteristic of being collected over a long period (2+ years), and it can be used for different Wi-Fi-based positioning studies. In addition, we also describe the solution (Wireless Sensor Network (WSN) + mobile unit) developed to collect this dataset, allowing researchers to replicate the method and collect similar datasets in other spaces.


Assuntos
Reprodutibilidade dos Testes , Simulação por Computador
6.
Environ Monit Assess ; 195(1): 129, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36409399

RESUMO

This study is aimed at evaluating C and N stocks in fractions of soil organic matter (SOM) in an area of bauxite mining under recovery with tree species. We have analyzed the long-term recovery of C and N stocks of organic matter fractions from five types of forest cover (Eucalyptus, Anadenanthera peregrina, mixed plantation of 16 native species, a mined area without vegetation cover as a control site, and a natural forest cover as a reference site). The total organic C (TOC) and N (TN) stocks and also organic matter fractions, particulate organic matter (POM), mineral-associated organic matter (MAOM), microbial biomass (MB), and labile C (LC), were determined, as well as the C/N ratio and the carbon management index (CMI). Although the stocks of TOC and LC, CMI, and MB did not differ between the types of forest cover in the 0-60 cm layer, they were lower than the values in the native forest. Forest cover increases the stocks of TOC, LC, MB, and CMI in the area of bauxite mining compared to the control site. In addition, we found that the TOC C and TN stocks and also SOM fractions (LC, C-MAOM, C-POM, N-MAOM, and N-POM) are positively correlated (r ≥ 0.71 for all cases) with volume of roots larger than 2 mm. Therefore, Eucalyptus, A. peregrina, and a mixed of 16 native trees contribute for restoring stocks of soil C and N following bauxite mining in the Brazilian Atlantic Forest.


Assuntos
Óxido de Alumínio , Eucalyptus , Biomassa , Monitoramento Ambiental , Florestas , Solo , Carbono/análise , Árvores
7.
Trop Anim Health Prod ; 49(8): 1715-1722, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28861677

RESUMO

Leptospirosis is a bacterial zoonotic disease that causes severe reproductive problems in livestock and generates economic losses for farmers. This study aimed to determine the seroprevalence of anti-Leptospira antibodies in small mammals, both wild and domestic, in two distinct areas of the semi-arid region of northeastern Brazil: the National Park of Serra das Confusões (NPSC), state of Piauí, a preserved area; and rural areas in the municipalities of Petrolina and Lagoa Grande, state of Pernambuco, non-preserved areas. Serum samples were evaluated using the microscopic agglutination test (MAT). Approximately 4% (6/152) of the wild animals were positive, all of them in the non-preserved area. Overall, the seroprevalence rates among goats and sheep were 13.4 (77/576) and 4.6% (24/518), respectively, confirmed in both areas. The seroprevalence rates in dogs and cats were 5.6 (10/180) and 4.7% (2/43) and were determined only in the non-preserved area. The risk factors associated with Leptospira spp. infection were as follows: ages of 1-3 and > 3 years for goats and sheep, region (preserved area) for goats, intensive management system for sheep, and region (non-preserved area) for dogs and wildlife. The present study confirmed the presence of circulation of Leptospira spp. in both of these areas of the Caatinga biome, as well as a variety of serotypes in these areas.


Assuntos
Animais Domésticos , Animais Selvagens , Leptospira/isolamento & purificação , Leptospirose/veterinária , Animais , Anticorpos Antibacterianos/sangue , Brasil/epidemiologia , Leptospirose/epidemiologia , Leptospirose/microbiologia , Prevalência , Estudos Soroepidemiológicos , Sorogrupo
8.
J Environ Qual ; 45(6): 1988-1997, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27898793

RESUMO

The development of efficient fertilizers with a diminished environmental footprint will help meet the increasing demand for food and nutrients by a growing global population. Our objective was to evaluate whether an acidic mine waste (AMW) could be used beneficially by reacting it with sparingly soluble phosphate rocks (PRs) to produce more soluble P fertilizer materials. Three PRs from Brazil and Peru were reacted with different concentrations of AMW. Changes in mineralogy and P species were determined using a combination of X-ray diffraction and phosphorus K-edge XANES spectroscopy, in addition to extractable P concentrations. Increasing the AMW concentration typically increased extractable P. X-ray diffraction data showed transformation of apatite to other species when PRs were reacted with AMW at ≥50% (v/v) in water, with gypsum or anhydrite forming at AMW concentrations as low as 12.5%. Linear combination fitting analysis of X-ray absorption near edge structure spectra also indicated a progressive transformation of apatite to noncrystalline Fe(III)-phosphate and more soluble Ca-phosphates with increasing AMW concentration. Because this AMW is costly to dispose of, reacting it with PR to produce a higher-grade phosphate fertilizer material could decrease the environmental impacts of the AMW and diminish the consumption of pure acids in conventional P fertilizer production.


Assuntos
Fosfatos/química , Eliminação de Resíduos Líquidos , Compostos Férricos , Fertilizantes , Concentração de Íons de Hidrogênio , Fósforo , Água
9.
J Environ Manage ; 166: 140-6, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26496844

RESUMO

Preventive and effective waste management requires cleaner production strategies and technologies for recycling and reuse. Metallurgical industries produce a great amount of acid effluent that must be discarded in a responsible manner, protecting the environment. The focus of this study was to examine the use of this effluent to increase reactivity of some phosphate rocks, thus enabling soluble phosphate fertilizer production. The effluent was diluted in deionized water with the following concentrations 0; 12.5; 25; 50; 75% (v v(-1)), which were added to four natural phosphate rocks: Araxá, Patos, Bayovar and Catalão and then left to react for 1 h and 24 h. There was an increase in water (PW), neutral ammonium citrate (PNAC) and citric acid (PCA) soluble phosphorus fractions. Such increases were dependent of rock type while the reaction time had no significant effect (p < 0.05) on the chemical and mineralogical phosphate characteristics. Phosphate fertilizers with low toxic metal concentrations and a high level of micronutrients were produced compared to the original natural rocks. The minimum amount of total P2O5, PNAC and PW, required for national legislation for phosphate partially acidulated fertilizer, were met when using Catalão and the effluent at the concentration of 55% (v v(-1)). Fertilizer similar to partially acidulated phosphate was obtained when Bayovar with effluent at 37.5% (v v(-1)) was used. Even though fertilizers obtained from Araxá and Patos did not contain the minimum levels of total P2O5 required by legislation, they can be used as a nutrient source and for acid effluent recycling and reuse.


Assuntos
Ácido Cítrico/química , Fertilizantes/análise , Resíduos Industriais/análise , Metalurgia , Fosfatos/química , Compostos de Amônio Quaternário/química , Solubilidade
10.
Appl Environ Microbiol ; 80(10): 3081-5, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24610849

RESUMO

During fungal rock phosphate (RP) solubilization, a significant quantity of fluoride (F(-)) is released together with phosphorus (P), strongly inhibiting the process. In the present study, the effect of two F(-) adsorbents [activated alumina (Al2O3) and biochar] on RP solubilization by Aspergillus niger was examined. Al2O3 adsorbed part of the F(-) released but also adsorbed soluble P, which makes it inappropriate for microbial RP solubilization systems. In contrast, biochar adsorbed only F(-) while enhancing phosphate solubilization 3-fold, leading to the accumulation of up to 160 mg of P per liter. By comparing the values of F(-) measured in solution at the end of incubation and those from a predictive model, it was estimated that up to 19 mg of F(-) per liter can be removed from solution by biochar when added at 3 g liter(-1) to the culture medium. Thus, biochar acted as an F(-) sink during RP solubilization and led to an F(-) concentration in solution that was less inhibitory to the process. In the presence of biochar, A. niger produced larger amounts of citric, gluconic, and oxalic acids, whether RP was present or not. Our results show that biochar enhances RP solubilization through two interrelated processes: partial removal of the released F(-) and increased organic acid production. Given the importance of organic acids for P solubilization and that most of the RPs contain high concentrations of F(-), the proposed solubilization system offers an important technological improvement for the microbial production of soluble P fertilizers from RP.


Assuntos
Aspergillus niger/metabolismo , Carvão Vegetal/química , Ácido Cítrico/metabolismo , Fluoretos/toxicidade , Sedimentos Geológicos/química , Gluconatos/metabolismo , Ácido Oxálico/metabolismo , Fósforo/metabolismo , Adsorção , Fluoretos/química , Fósforo/química , Solo/química , Microbiologia do Solo , Solubilidade
11.
Int J Biol Macromol ; 257(Pt 1): 128374, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38052289

RESUMO

Cactus pear cladodes, clones 'Miúda' (MIU) and 'Orelha de Elefante Mexicana' (OEM) were harvested at 6 am and 8 pm during the rainy-dry, dry and rainy seasons to evaluate the effect of type of clone and harvest seasons on the physicochemical and technological properties of mucilage as well as the optical, physicochemical, mechanical, thermal and microstructural characteristics of the films obtained. The mucilage of the OEM clone presented a higher content of phenolic compounds, compared to the Nopalea genus, regardless of the season and time of harvest. Furthermore, the dry period resulted in higher carbohydrate levels, regardless of the harvest time. The biopolymeric films produced from the OEM clone harvested in the rainy season and rainy-dry transition showed darker color, better mechanical properties, water barrier, compact microstructure and thermal stability when compared to the MIU clone. Furthermore, harvesting at 6 am provided improvements in the mechanical conditions, permeability and thermal stability of the films of both types of clones studied. These results showed strong environmental modulation, naturally incorporating important macromolecules such as carbohydrates and phenolic compounds, used in the industry in the production of nutraceutical foods, into the mucilage. Furthermore, harvesting cladodes at 6 am in the rainy and transitional (rainy-dry) periods provided better quality biopolymeric films and/or coatings.


Assuntos
Opuntia , Opuntia/química , Estações do Ano , Polissacarídeos , Carboidratos , Água
12.
Appl Environ Microbiol ; 79(16): 4906-13, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23770895

RESUMO

The simultaneous release of various chemical elements with inhibitory potential for phosphate solubilization from rock phosphate (RP) was studied in this work. Al, B, Ba, Ca, F, Fe, Mn, Mo, Na, Ni, Pb, Rb, Si, Sr, V, Zn, and Zr were released concomitantly with P during the solubilization of Araxá RP (Brazil), but only F showed inhibitory effects on the process at the concentrations detected in the growth medium. Besides P solubilization, fluoride decreased fungal growth, citric acid production, and medium acidification by Aspergillus niger. At the maximum concentration found during Araxá RP solubilization (22.9 mg F(-) per liter), fluoride decreased P solubilization by 55%. These findings show that fluoride negatively affects RP solubilization by A. niger through its inhibitory action on the fungal metabolism. Given that fluoride is a common component of RPs, the data presented here suggest that most of the microbial RP solubilization systems studied so far were probably operated under suboptimal conditions.


Assuntos
Aspergillus niger/metabolismo , Fosfatos/metabolismo , Brasil , Fluoretos/metabolismo , Concentração de Íons de Hidrogênio , Espectrometria de Massas , Microbiologia do Solo , Solubilidade , Espectrofotometria Atômica
13.
World J Microbiol Biotechnol ; 29(1): 43-50, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22927013

RESUMO

The effects of different doses of rock phosphate (RP), sucrose, and (NH(4))(2)SO(4) on the solubilization of RP from Araxá and Catalão (Brazil) by Aspergillus niger, Penicillium canescens, Eupenicillium ludwigii, and Penicillium islandicum were evaluated in a solid-state fermentation (SSF) system with sugarcane bagasse. The factors evaluated were combined following a 2(3) + 1 factorial design to determine their optimum concentrations. The fitted response surfaces showed that higher doses of RP promoted higher phosphorus (P) solubilization. The addition of sucrose did not have effects on P solubilization in most treatments due to the presence of soluble sugars in the bagasse. Except for A. niger, all the fungi required high (NH(4))(2)SO(4) doses to achieve the highest level of P solubilization. Inversely, addition of (NH(4))(2)SO(4) was inhibitory to P solubilization by A. niger. Among the fungi tested, A. niger stood out, showing the highest solubilization capacity and for not requiring sucrose or (NH(4))(2)SO(4) supplementation. An additional experiment with A. niger showed that the content of soluble P can be increased by adding higher RP doses in the medium. However, P yield decreases with increasing RP doses. In this experiment, the maximal P yield (approximately 60 %) was achieved with the lower RP dose (3 g L(-1)). Our results show that SSF can be used to obtain a low cost biofertilizer rich in P combining RP, sugarcane bagasse, and A. niger. Moreover, sugarcane bagasse is a suitable substrate for SSF aiming at RP solubilization, since this residue can supply the C and N necessary for the metabolism of A. niger within a range that favors RP solubilization.


Assuntos
Celulose/metabolismo , Fungos/metabolismo , Fosfatos/metabolismo , Saccharum/metabolismo , Brasil , Meios de Cultura , Fermentação , Fósforo/metabolismo , Solubilidade , Sacarose/metabolismo
14.
Heliyon ; 9(7): e18091, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37483791

RESUMO

In this work, poly (vinyl alcohol) (PVA) was employed to produce a Mesoporous Composition of Matter-48 Modified (MCM-48-M or MCM-48-PVA). After surface modification, MCM-48-M was used to produce nanocomposite (NC) films with polycaprolactone (PCL) as a matrix at room temperature. PCL and MCM-48 nanoparticles (NPs) were chosen due to their great biocompatibility and low toxicity. However, MCM-48-M is more compatible with PCL than MCM-48. NC films were sterilized by gamma radiation with a dose of 25 kGy and characterized by experimental techniques to investigate their chemical, mechanical (tensile) and thermal properties. Scanning electron microscopy (SEM) and transmission electronic microscopy (TEM) results indicated that MCM-48-M exhibited a random distribution in the PCL matrix. The PCL chemical structure was preserved in NC films as described by Fourier transform infrared (FT-IR) spectroscopy as well as the tensile and thermal properties of NC films. FT-IR and thermogravimetric analysis (TGA) results showed surface modification. X-ray diffraction (XRD) and differential scanning calorimetry (DSC) showed that crystalline symmetries were preserved and the crystallinity of NC films had small variations in all samples before and after irradiation, respectively. But, our results did not indicate major changes showing that this method is successful for the sterilization of PCL/MCM-48-PVA NC films.

15.
Front Med (Lausanne) ; 9: 893642, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35572967

RESUMO

Introduction: Plasma free hemoglobin is the gold standard for monitoring hemolysis in extracorporeal membrane oxygenation (ECMO) but its routine use has some limitations. Carboxyhemoglobin (HbCO) is also a marker of intravascular hemolysis. We aimed to investigate HbCO as a marker of both hemolysis and oxygenator dysfunction in patients supported by ECMO. Methods: Retrospective analysis of patients on ECMO in an adult ICU in a tertiary hospital. HbCO was recorded every 6 h in the 48 h before and after oxygenator change in adult patients on ECMO support with an oxygenator dysfunction and replacement. Results: The investigation of 27 oxygenators replacements in 19 patients demonstrated that HbCO values progressively increased over time and then significantly decreased after oxygenator change. Median oxygenator lifespan was 14 days [interquartile range (IQR) 8-21] and there was no correlation between HbCO and oxygenator lifespan [Spearman coefficient 0.23 (p = 0.23)]. HbCO values at oxygenator change [HbCO median 2.7 (IQR 2.5-3.5)] were significantly higher than the HbCO values 1 week before [HbCO median 2.07 (IQR 1.86-2.8)] (p value < 0.001). Conclusion: Our data highlight the potential role of HbCO as a novel marker for ECMO oxygenator dysfunction.

16.
PLoS One ; 17(3): e0266174, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35344570

RESUMO

BACKGROUND: Intensive Care Unit (ICU) patients are known to lose muscle mass and function during ICU stay. Ultrasonography (US) application for the assessment of the skeletal muscle is a promising tool and might help detecting muscle changes and thus several dysfunctions during early stages of ICU stay. MUSiShock is a research project aiming to investigate structure and function of diaphragm and peripheral muscles using ultrasound techniques in septic shock patients, and to assess their relevance in several clinical outcomes such as the weaning process. METHODS AND DESIGN: This is a research protocol from an observational prospective cohort study. We plan to assess eighty-four septic shock patients during their ICU stay at the following time-points: at 24 hours of ICU admission, then daily until day 5, then weekly, at extubation time and at ICU discharge. At each time-point, we will measure the quadriceps rectus femoris and diaphragm muscles, using innovative US muscle markers such as Shear-Wave Elastography (SWE). In parallel, the Medical Research Council (MRC) sum score for muscle testing and the Airway occlusion pressure (P0.1) will also be collected. We will describe the association between SWE assessment and other US markers for each muscle. The association between the changes in both diaphragm and rectus femoris US markers over time will be explored as well; finally, the analysis of a combined model of one diaphragm US marker and one limb muscle US marker to predict weaning success/failure will be tested. DISCUSSION: By using muscle ultrasound at both diaphragm and limb levels, MUSiShock aims to improve knowledge in the early detection of muscle dysfunction and weakness, and their relationship with muscle strength and MV weaning, in critically ill patients. A better anticipation of these short-term muscle structure and function outcomes may allow clinicians to rapidly implement measures to counteract it. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04550143. Registered on 16 September 2020.


Assuntos
Diafragma , Choque Séptico , Estado Terminal , Diafragma/diagnóstico por imagem , Humanos , Unidades de Terapia Intensiva , Debilidade Muscular , Estudos Observacionais como Assunto , Estudos Prospectivos , Choque Séptico/diagnóstico por imagem , Tecnologia , Ultrassonografia/métodos
17.
Physiol Rep ; 9(17): e15012, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34491003

RESUMO

OBJECTIVE: The present study investigates whether ScvO2 variations induced by passive leg raising (PLR) are able to predict fluid responsiveness (FR) in mechanically ventilated patients. DESIGN: A monocentric prospective clinical study. SETTING: An intensive care division in a tertiary hospital. PATIENTS: The inclusion criteria were elective postoperative cardiac surgery patients who were over 18 years old, deeply sedated, mechanically ventilated and needed volume expansion (VE). Fluid responders (R) were defined as patients who increased their left ventricular outflow tract velocity time integral (VTI) ≥15% after VE. INTERVENTION: In patients included in this study, continuous ScvO2  monitoring (CeVOX device, Pulsion Medical Systems) and VTI (transthoracic echocardiography) were measured simultaneously before and during a PLR test and before and after VE (with 500 ml of saline). MEASUREMENTS AND MAIN RESULTS: Thirty-three consecutive patients were included in this study. In 15 patients with a positive PLR test (increase in VTI ≥15%), ScvO2 increased during PLR by 9 ± 4%. In the 18 patients with a negative PLR test, ScvO2 did not significantly change during PLR. VE increased ScvO2 by 9 ± 6% and 2 ± 4% in responders and nonresponders, respectively. If ScvO2 increased by >4% during the PLR test, then a positive VTI response (≥15%) was diagnosed with a sensitivity of 93% (68-99%) and a specificity of 94% (63-99%) (Area under the receiver operating characteristic curve 0.92 ± 0.58, p < 0.05). Moreover, ScvO2 variations were able to distinguish responders to VE from nonresponders to VE with a sensitivity of 87% (68-99%) and a specificity of 89% (63-99%) (Area under the receiver operating characteristic curve 0.89 ± 0.07, p < 0.05). CONCLUSIONS: ScvO2 variation induced by PLR is a reliable, minimally invasive parameter for predicting FR at the postoperative cardiac surgery bedside of mechanically ventilated, critically ill patients.


Assuntos
Estado Terminal/terapia , Hidratação/métodos , Perna (Membro)/fisiologia , Saturação de Oxigênio/fisiologia , Posicionamento do Paciente/métodos , Amplitude de Movimento Articular/fisiologia , Idoso , Débito Cardíaco/fisiologia , Ecocardiografia/métodos , Eletrocardiografia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oximetria/métodos , Valor Preditivo dos Testes , Estudos Prospectivos , Respiração Artificial/métodos , Volume de Ventilação Pulmonar/fisiologia , Resultado do Tratamento
18.
Physiol Rep ; 9(4): e14737, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33611854

RESUMO

Type A lactic acidosis is a potentially life-threatening complication in critically ill patients and is the hallmark of a shock state as a result of tissue hypoperfusion and dysoxia. Type B lactic acidosis results from mechanisms other than dysoxia and is a rare condition in patients with solid tumors or hematological malignancies. We present a case of a 60-year-old man with lactic acidosis who was found to have a Burkitt lymphoma related to a posttransplant lymphoproliferative disorder. Lactagenic cancers are characterized by increased aerobic glycolysis and excessive lactate formation, a phenomenon described by Warburg in 1923 that is correlated with cancer aggressiveness and poor survival. There is increased glucose utilization with the purpose of lactagenesis under fully oxygenated conditions, as lactate seems to be a potent signaling molecule for angiogenesis, immune escape, cell migration, metastasis and self-sufficient metabolism, which are five essential steps of carcinogenesis. Type B lactic acidosis in association with malignancies carries an extremely poor prognosis. Currently, effective chemotherapy seems to be the only hope for survival.


Assuntos
Equilíbrio Ácido-Base , Acidose Láctica/etiologia , Linfoma de Burkitt/complicações , Efeito Warburg em Oncologia , Acidose Láctica/diagnóstico , Acidose Láctica/metabolismo , Acidose Láctica/fisiopatologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma de Burkitt/diagnóstico , Linfoma de Burkitt/tratamento farmacológico , Linfoma de Burkitt/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Indução de Remissão , Resultado do Tratamento
19.
Phys Ther ; 101(1)2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33492400

RESUMO

OBJECTIVE: The aim of this case series was to describe the experience of Swiss physical therapists in the treatment of patients with COVID-19 during their acute care hospital stay and to discuss challenges and potential strategies in the clinical management of these patients. METHODS: We report 11 cases of patients with COVID-19 from 5 Swiss hospitals that illustrate the various indications for physical therapy, clinical challenges, potential treatment methods, and short-term response to treatment. RESULTS: Physical therapists actively treated patients with COVID-19 on wards and in the intensive care unit. Interventions ranged from patient education, to prone positioning, to early mobilization and respiratory therapy. Patients were often unstable with quick exacerbation of symptoms and a slow and fluctuant recovery. Additionally, many patients who were critically ill developed severe weakness, postextubation dysphagia, weaning failure, or presented with anxiety or delirium. In this setting, physical therapy was challenging and required specialized and individualized therapeutic strategies. Most patients adopted the proposed treatment strategies, and lung function and physical strength improved over time. CONCLUSION: Physical therapists clearly have a role in the COVID-19 pandemic. Based on our experience in Switzerland, we recommend that physical therapists routinely screen and assess patients for respiratory symptoms and exercise tolerance on acute wards. Treatment of patients who are critically ill should start as soon as possible to limit further sequelae. More research is needed for awake prone positioning and early breathing exercises as well as post-COVID rehabilitation. IMPACT: To date, there are few data on the physical therapist management of patients with COVID-19. This article is among the first to describe the role of physical therapists in the complex pandemic environment and to describe the potential treatment strategies for countering the various challenges in the treatment of these patients.


Assuntos
COVID-19/terapia , Cuidados Críticos/métodos , Estado Terminal/terapia , Fisioterapeutas/organização & administração , Modalidades de Fisioterapia/organização & administração , Feminino , Humanos , Unidades de Terapia Intensiva , Masculino , Força Muscular , Posicionamento do Paciente , Suíça
20.
Chemosphere ; 285: 131468, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34271465

RESUMO

Changes in lead (Pb) speciation in the rhizosphere may be plant species-dependent and dictate Pb fate and behavior in the soil-plant system. X-ray absorption near edge structure (XANES) spectroscopy can explain how these changes affect Pb availability in soils and its uptake by plants. We investigated the changes in Pb speciation and availability in the rhizosphere of eucalypt (Eucalyptus urophylla x Eucalyptus grandis), palisade grass (Urochloa brizantha cv. Marandu), and Indian mustard (Brassica juncea L.) using XANES spectroscopy. A greenhouse experiment was performed in a complete randomized design, with three plant species and a no plant control treatment. After three months, rhizosphere and bulk soil samples were collected, Pb speciation was assessed by Pb L3-edge XANES spectroscopy, and Pb concentration was determined in plant tissue. In bulk soil, we found Pb primarily as Pb-Il (Pb sorbed to illite; 48%) and lead monoxide (PbO; 36%). In the rhizosphere, Pb-Ka (Pb sorbed to kaolinite; 33-56%) and (CH3COO)2Pb (25-41%) were the main Pb forms, the latter suggesting Pb complexation by low molecular weight organic acids (LMWOAs). Palisade grass rhizospheric soil had a lower abundance of Pb-Ka and a higher abundance of (CH3COO)2Pb than eucalypt and mustard, which led to low Pb concentration in plant tissue. LMWOAs exudation followed by Pb2+ complexation is the apparent mechanism used by palisade grass to detoxify the rhizosphere and control Pb uptake. Given its low Pb uptake and potential to complex Pb in organic forms, palisade grass may be a promising species for Pb phytostabilization in contaminated soils.


Assuntos
Poluentes do Solo , Poluição Ambiental , Chumbo , Raízes de Plantas/química , Distribuição Aleatória , Rizosfera , Solo , Poluentes do Solo/análise
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